EXCAVATION WORK ROD

PROBLEM TO BE SOLVED: To surely and easily connect a hydraulic supply path of a screw auger rod against wobbling in a rotating direction of a joint engaging part by matching displacement generated from a gap of male and female joints and absorbing a relief margin.SOLUTION: In an excavation work rod provided with a male coupler 117 inside a male joint 102 of a rod 100 including a hydraulic supply path 108 in the inside and provided with a female coupler 118 inside a female joint 103, the hydraulic supply path 108 comprises a hydraulic hose, a projected guide is formed at the male coupler 117, a projected guide groove is formed at the female coupler 118, detachment is prevented by a stopper of the female coupler 118 and a bearing is freely rotatably provided in the female coupler 118. An end of an outer peripheral part cover pipe 112 of hydraulic piping 111 is fitted to a bearing 5 and the female coupler 118, the cover pipe 112 and the bearing are fixed with a set machine screw, and a positioning pin for turning the positioning hole of the cover pipe 112 to a loose hole is screwed to the outer periphery of the female coupler 118.